Cinder pot



w. JOHNSTON. JR

Y CINDER POT Filed Jan. 27, 1934 2 Sheets-Sheet 2 w I INVENTOR j! a /w g;

Patented Oct. 13, 1936 NlTED STATES A PATENT OFFICE This invention relates to pots such as are employed in handling molten slag and cinder and which are known in the art as cinder, pots.

Heretofore cinder pots have been cast with 5 straight sides and of circular cross-section and such pots were open to the objection that the metal in the walls thereof grew and bulged and caused the pots eventually to crack. These bulges aside from being objectionable in that 10 they caused the pots to crack, were also objectionable in that the skull which formed on the inner surface of the pot became so anchored in these bulges that it was almost impossible to remove it.

15 An object of this invention is the provision of a cinder pot of such design and construction as to avoid cracking and bulging and the difliculties encountered in the removal of skull which such bulging occasions.

20 Another object of the invention is the provision of a cinder pot of such construction and design that it may be used for a longer period of time without cracking than has heretofore been possible with prior art cinder pots and 25 which may be made lighter in weight without sacrificing the necessary strength required in such pots.

Another object of the invention is the provision of a cinder pat'of such construction and 3 design that the casting thereof is facilitated to the extent that, when finished, it will-not be subjected to the internal stresses that occur in prior art pots if great care is not taken in the cooling of the pots after casting.

35 Other objects of the invention will, in part,

be apparent and will, in part, be obvious from the following description taken in conjunction with the accompanying drawings, in which:

Figure 1 is a view partly in side elevation and 40 partly in section of a receptacle embodying one form of the invention;

Fig. 2 is a fragmentary top plan view of the receptacle shown in Fig. ,1;

Fig. 3 is a fragmentary view in side elevation of receptacle embodying a modified form of'the invention, the receptacle being mounted in a trunnion ring; and

Fig. 4 is a view in section of the receptacle taken on line IV-IV of Fig. 3. 50 Throughout the drawings and specification,

like references indicate like parts.

In Figs. 1 and 2 of the drawings a receptacle i, of the type known in the art as a cinder or slag pot, is shown having a closed, thermo-ex- -55 pansively flexible bottom 2, and wall 3 which make possible long and continued handling of molten slag and cinders without causing the wall to bulge and/or crack.

The bottom 2 of the pot is preferably of spheroidal shape, while wall 3 is formed with a 5 plurality of corrugations 4, having inwardly and'outwardly projecting peaks 5 and 6, disposed circumferentially and extending longitudinally of the pot. It is preferred that the corrugations be of a form simulating a sinusoid and that the width and depth thereof gradually decrease from the rim towards thebottom 2.

As may be seen in Fig. 1, the outer surfaces of peaks 6 lie tangent to the outer surface of bottom 2 and that the inner surfaces of peaks 6 lie tangent to the inner surface of the bottom. These points of tangency occur at the intersec tion of radius R with the inner and outer surfaces of bottom 2.

The inner surfaces of peaks 5 also lie tangent to the inner surface of bottom 2 and the outer surfaces of these peaks lie tangent to the outer surface of the bottom. These points of tangency occur at the intersection of radius R1 with the inner and outer surfaces of the pot and the angle between R and R1 is equal to the angle between peaks 5 and 6.

A pot constructed as above described is flexible from the standpoint of thermal expansion and contraction for the reason that the bottom 2 being spheroidal in shape embodies the inherent thermo-expansively flexible properties of a.

sphere and that the corrugations 5 and 6 permit the pot wall to freely expand and contract circumferentially with changes in temperature.

Since the corrugations increase both in depth and width from their points of tangency with bottom portion 2, the actual circumferential length of wall section at successive horizontal planes increases at a greater rate than the change in diameter of the circles drawn tangent to the peaks of the corrugations at such planes. For these reasons pots embodying the above mentioned principles of construction will not develop bulges and/or cracks as the result of repeated and severe temperature reversals.

The particular pot herein illustrated is of the type designed primarily for use with slag cars or buggies and to this end is provided with support pads or lugs 8, spaced uniformly around the pot and located at or slightly above the middle thereof.- These support pads each comprises a horizontal flange 9 and two spaced vertical ribs In which rise from the opposite edges thereof to the wall of the pot. It is preferred that the support pads be formed on the ridge or peak of a corrugation both from the standpoint of convenience in casting with the pot and from the standpoint of placing the pads on the pot I at points where maximum strength in the wall section may be obtained. The horizontal flanges 8 of these support pads are provided with elongated apertures H for the reception of bolts that lock the pot to the support on which it may be mounted.

When a pot is mounted on a slag car or buggy, it is set in a. yoke or trunnion ring I2 such as shown in Fig. 3 so that the support pads rest on the yoke. The yoke embraces the pot and is provided with trunnions l3 disposed on a diameter of the yoke and the pot so that when a pot has been filled with slag or cinder and transported to the place of dumping, the pot may be turned about these trunnions and the contents emptied.

In the prior art pots above mentioned, the

bulging and cracking almost invariably occurred in a region above the point where the support pened that these slag pots, when filled with molten slag, were not immediately emptied and the slag was permitted to stand for such a length of time that a solidified or shell formed along the inside surface of the slag pot and this skin became thicker and thicker as the cooling period increased- When a pot was emptied, the molten slag ran out, but the skull being interlocked with the bulge in the pot would not dis: lodge and was almost impossible to remove.

With the type of pot herein shown and described, no bulging will occur in the pot wall and for this reason, the skull may be removed by tipping the pot upside down or by using a tool known in the art as a skull puller.

In Figs. 3 and 4, a pot I4 embodying a modi-- fled form of the invention is shown. In this pot the bottom portion and the wall are formed with corrugations 15, similar to those shown on pot l, except that corrugations l5 extend from the rim to the very bottom of the pot, i. e., the

lowermost ends of the corrugations converge at the vertical axis of the pot.- In other respects, pot is similar to pot I, as indicated by the use of similar reference characters.

The pots herein illustrated may be made cast iron, cast steel or cast alloy steel, but regardless of the kind of metal employed, the pots made in accordance with this invention have proved, by actual experience, that they will last longer without cracking or without developing the objectionable bulges above referred to, than the prior art type of pots, even though-such prior art pots were made of alloy steel or cast steel.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:-- I

1. A receptacle for slag comprising a pot hav- I ing a closed spheroidal bottom and upwardly diverging walls having longitudinal corrugations spaced circumferentially of the pot, the inner and outer surfaces of the lower ends of said corrugations being tangent to the inner and vided with a series of. ci-rcumferentially spaced.

corrugations which extend from a point near the bottom of the pot and terminate at the top thereof in a corrugated substantially unrestrained rim.

3. A' slag pot according to claim 2 characterized by the fact that the corrugations are relatively narrow and shallow at their lower .ends and increase both in width and depth from'their lower to their upper ends.

4. A cinder pot for receiving molten slag from blast and open hearth furnaces, said pot having a closed rounded bottom and upwardly diverging walls of substantially uniform thickness provided with circumferentially spaced corrugations extending. continuously from apoint adjacent said curved bottom to and terminating in a substantially unrestrained corrugated rim at the top of the pot, said corrugationsincreasing progressively both in depth and width from their lower to their upper ends.

5. A cinder pot for receiving molten slag 'fr blast and open hearth furnaces, said pot having a closed rounded bottom, and ,corrugated side walls, of substantially uniform thickness, the corrugations in the walls extending upwardly from'said curved bottom and merging into the trim, whereby the portion of the pot side walls.

extending from the rim to the curved bottom thereof are free to expand and contract with temperature changes without subjecting the side walls to such thermal stresses as cause permanent inward bulging and cracking.

6. A slag pot of generally circular contour in,

transverse section at any horizontal plane and having a rounded bottom and side walls of substantially uniform thicknem extending upwardly and outwardly at an angle to the vertical, characterized byrthe fact that the side walls and bottom are provided with a series of ,circumfer entially spaced corrugations which extend from the bottom of the pot and terminate at the top thereof in a corrugated substantially unrestrained rim.

7. A cinder pot for receiving molten slag from blast and open hearth furnaces, said pot having a closed rounded corrugated bottom and corrugated side walls, the corrugations in the walls and bottom extending upwardly and merging.

into the rim, whereby the corrugated portions of 

